2.45pm update

Cameron refuses to apologise to Ukip

David Cameron today refused to apologise for describing the UK Independence party as "fruitcakes", "loonies" and "closet racists".

The Conservative leader's remarks came after Ukip threatened to use the Freedom of Information Act to force him to reveal the names of individuals who have secretly lent money to the Conservative party.

"Ukip is sort of a bunch of ... fruitcakes and loonies and closet racists mostly," Mr Cameron told LBC radio.

Ukip's leader Roger Knapman said the attack on his party was a "sad, silly, stupid affair by ... Mr Cameron who is inexperienced as party leader and as a politician generally."

Nigel Farage MEP, Ukip's co-founder, described the remarks as "disgraceful. We demand an apology".

"We don't mind name-calling, it's politics, but in this day and age there are things you can't call people and racist is one of them," he said.

"Fruit cakes and loonies we can live with - we have a sense of humour - but we draw the line at his unfounded accusations of racism." He demanded to know "where and when" Mr Cameron was accusing the party of racism.

"We haven't said or done anything remotely racist. We've just elected Delroy Young [who is black] to our NEC." He said the party had many black members who would be offended by the allegation.

"Unless he apologises, we're not ruling anything out." The party was "not going to dash straight to the lawyers" but it would not let the matter drop, Mr Farage added.

But Mr Cameron defended his remarks before a meeting in Leeds today. "I don't think I'm saying anything that hasn't been said before. Ukip have some issues - not least that their own founding member Dr [Alan] Sked left the party because he thought they had been infiltrated by the far right ... I was making a general point that they are the 'stop the world I want to get off' party."

One of Mr Cameron's advisers, George Eustice, stood for Ukip in the 1999 European elections and went on to lead the No campaign against British entry to the euro. "We're waiting for his call," Mr Farage said today.

Eric Pickles, the deputy chairman of the Conservative party, backed Mr Cameron, saying he had a "legitimate point" and Ukip had had "too easy a deal".

Ukip wrote to the information commissioner yesterday to ask for the details of the Conservative loans to be released. David Campbell Bannerman, the party chairman, argues that the disclosure of the information would be in the public interest.

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